<?php
$a = 5;
$b = 3;
echo "$a + $b = ".($a+$b)."<br>";
echo "$a - $b = ".($a-$b)."<br>";
echo "$a * $b = ".($a*$b)."<br>";
echo "$a / $b = ".($a/$b)."<br>";
echo "$a % $b = ".($a%$b)."<br>";
$a++;// 进行递减
echo "$a ++ = $a<br>";
$b--;// 进行递减
echo "$b -- = $b<br>";